A key issue facing the families of those injured in the Berkeley tragedy is when they can be flown back to Ireland to continue their treatment.

However, the seven students face a "long road to recovery" as they receive round-the-clock care, according to one hospital source.

The survivors are being cared for at Highland Hospital in Oakland; Eden Medical Center in Castro Valley; and John Muir Medical Center in Walnut Creek.

While the severity of their injuries varies greatly, medical sources last night confirmed some have "a long and difficult few months ahead of them".

"I will not go into the specific details due to patient confidentiality, but it's safe to say their young bodies suffered severe trauma," explained a source.

"In some instances there's skeletal and nerve damage; they fell from quite a height.

"They're being closely monitored by medical staff. The physical injuries are one thing; the psychological toll is sometimes as difficult to overcome. The memories of that night will be with them forever."

Given the complexity of many of the injuries, he said it is far too early to say how long they will remain in hospital in the US.

Meanwhile, patients and their families could face massive medical bills.

While medical insurance is mandatory for all J1 visa holders, it is feared that costs could still mount for the injured. It is not clear if the students' health policies will completely cover all healthcare costs incurred as a result of the tragedy.

The US health system is synonymous with extremely high medical bills.

One day as an in-patient can cost an average of more than $4,000.

Aoife Beary

Aoife has undergone surgery in Highland Hospital, about 25 kilometres from the scene of the accident.

The 21-year-old from Blackrock in south Dublin faces a long and difficult battle and may require further operations as part of her rehabilitation. Her parents are at her bedside.

Conor Flynn

While the 22-year-old is expected to make a full recovery, it is understood he will require extensive physiotherapy sessions in the months ahead.

Minister for the Diaspora Jimmy Deenihan said he was "very encouraged with the spirit" that he saw in the young man when he visited him in hospital.

Clodagh Cogley

The 21-year-old suffered extensive injuries to her legs and spine, and while they are not life-threatening, she is likely to undergo extensive physiotherapy treatment.

Her family have publicly thanked Jack Halpin who grabbed her as they tumbled towards the ground, breaking her fall.

Jack Halpin

Jack (21) is in hospital alongside his friend Conor Flynn and is expected to make a good recovery.

However, Jack's progress has been slower, and he is likely to spend many weeks in hospital. He is now being treated for back injuries and he sustained two broken legs during the horrific accident.

Sean Fahey

The former St Mary's College Dublin student is said to be "recovering well" from his injuries in Eden Medical Centre.

Two of the deceased, Eoghan Culligan and Niccolai Schuster, also attended the school. The student has since taken to social media to "thank everyone for their support in such a dark time".

Hannah Waters

The DCU student is one of two survivors who suffered the most extensive injuries following the balcony collapse.

The 21-year-old has undergone a range of tests and a number of surgical procedures.

However, her family are said to remain hopeful that her condition will continue to improve.

Niall Murray

NUIG student Niall was continuing his recovery in the Eden Medical Centre last night, alongside Sean Fahey and Clodagh Cogley.

The trio were considered to have escaped the worst of the injuries, but medics have stressed they suffered serious injuries in the 40ft fall.